Abstract: There is provided a process for preparing a compound of the formula ##STR1## wherein X.sup.1, X.sup.2, X.sup.3, and X.sup.4 are independently selected from the group consisting of fluorine, chlorine, bromine and iodine; n is an integer of from 1 to about 100; a, b, c, and d are each integers of from about 0 to about 4; Z.sup.1 and Z.sup.2 are independently selected from the group consisting of halogen and alkyl of from about 1 to about 15 carbon atoms; R.sup.1 and R.sup.2 are independently selected from the group consisting of alkylene containing from about 1 to about 12 carbon atoms, alkylenyl containing from about 2 to about 12 carbon atoms, cycloalkylene of the formula ##STR2## wherein R.sup.3, R.sup.4 and R.sup.5 are independently selected from the group consisting of alkylene of from about 1 to about 5 carbon atoms, and cycloalkylenyl of the formula ##STR3## and A is selected from the group consisting of R.sup.3 CR.sup.